The present invention relates to a data storage tape cartridge for use with a tape drive as part of a tape drive system. More particularly, it relates to a single reel data storage tape cartridge having datum pads that provide enhanced registration and alignment with the tape drive.
Data storage tape cartridges and tape drive systems have been used for decades in the computer, audio, and video fields to record and store large volumes of information for subsequent retrieval and use. In general terms, a data storage tape drive system includes a data storage tape cartridge and a tape drive. The data storage tape cartridge consists basically of an outer shell or housing maintaining at least one tape reel and a length of magnetic storage tape. The storage tape is wrapped about a hub portion of the tape reel(s) that, in turn, is rotatably disposed within the housing. The housing typically includes a separate cover and base, the combination of which forms an opening (or window) at a forward portion thereof for allowing access to the storage tape upon insertion of the tape cartridge into the tape drive. The tape drive includes transducers, such as magnetic read/write heads, for recording data to, or reading data from, the storage tape.
The interaction between storage tape and heads may take place within the housing (for example, with a mid-tape load design). With this approach, the cartridge includes two tape reels to drive the storage tape through a precise tape path relative to the window. Because the tape path is essentially confined to the housing, the tape drive cannot readily compensate for positioning errors of the tape cartridge relative to the tape drive. In light of this constraint, numerous efforts have been made to incorporate registration features into dual reel tape cartridges, and related tape drives.
An alternative tape drive system technique is to direct the storage tape outwardly and away from the cartridge housing to an adjacent area within the tape drive at which the read/write head(s) is located. With this approach, the tape cartridge has a single tape reel about which the storage tape is wrapped. Further, a leader block is secured to a leading end of the storage tape, and is configured for engagement with a threader mechanism and take-up reel associated with the tape drive. The threader mechanism directs the leader block, and thus the storage tape, out from the cartridge housing, through a tape path that includes interaction with the read/write head(s), and to the take-up reel. As compared to a dual reel design, a single reel tape cartridge can maintain an increased length of storage tape, and requires less housing space.
Because the tape path is essentially defined by the tape drive, existing single reel tape drive systems are unconcerned with precise registration of the tape cartridge to the tape drive. More particularly in addition to the take-up reel used to engage the leader block, the single reel tape drive includes a drive hub configured to engage and rotate the tape reel, along with a receiving frame within which the data storage tape cartridge is inserted. The receiving frame only generally positions the tape cartridge relative to, or above, the drive hub that is then maneuvered so as to engage the tape reel. To this end, single reel prior tape drive systems compensate for certain variations in positioning of the tape cartridge, and in particular the tape reel, relative to the drive hub. For example, with currently available single reel/hub tape drives, the drive hub typically has vertical movement capabilities in the range of approximately 0.5 inch, as well as an ability to accommodate radial alignment deviations on the order of 0.1 inch. Thus, the drive hub can be maneuvered to account for misalignments with the tape reel. Further, even if the drive hub is slightly off-center relative to an axis or center of the tape reel upon engagement therebetween, this misalignment has little affect on positioning of the storage tape relative to the read/write head(s) as the storage tape is directed through a tape path (or extension from the cartridge housing) having a length in upwards of 12 inches, providing a sufficient distance along which storage tape positioning corrections can be made.
As with other technology-based industries, evolution of data storage tape drive systems is focused upon increased capacity and operational speed, while at the same time reducing an overall size of the system. For example, efforts have been made to reduce the size of tape drives for use with single reel data storage tape cartridges. Implementation of this desired goal requires greatly reducing a length of the tape path (or distance that the storage tape is extended from the cartridge housing) to approximately 1 inch. Similarly, drive hubs have been redesigned to allow for only slight movements, on the order of 0.1 inch vertically and 0.01 inch in all other directions, it being understood that a reduction of even 0.001 inch can have a significant effect on the overall tape drive size. These alterations have placed a greater emphasis on precise alignment of the tape cartridge, and in particular the tape reel, relative to the drive hub upon insertion within the tape drive. Unfortunately, currently available single reel data storage tape cartridges and related tape drives cannot provide for this now necessary, precise alignment.
In addition to satisfying registration requirements, any newly designed single reel data storage tape cartridge must remain compatible with other handling equipment commonly employed. For example, library systems, available for example from Storage Technology Corp. of Louisville, Colo. are utilized to organize and store a large volume of data storage tape cartridges. In this regard, the library system typically includes a housing that maintains a series of individual cartridges at known positions for retrieval by a robotic pick-and-place device. In this regard, the housing includes xe2x80x9cstandardxe2x80x9d positioning features that locate each individual cartridge at a position that is xe2x80x9cknownxe2x80x9d by the robot. Thus, any newly designed data storage tape cartridge must be configured for proper interaction with these standard positioning features.
Single reel data storage tape drive systems have evolved to the point where precise cartridge/drive alignment is now required. Unfortunately, currently available single reel cartridges are not designed to provide this precise alignment. Therefore, a need exists for a single reel data storage tape cartridge and associated tape drive that facilitates precise registration and preferably is compatible with other commonly used handling devices.
One aspect of the present invention relates to a data storage tape cartridge including a housing, a single tape reel, a storage tape, and a leader block. The housing includes a front, a back, a first side, a second side, a top, and a bottom. Further, the housing forms a leader block window, a lateral datum pad, and a longitudinal datum pad. The leader block window is formed at a corner defined by the front and the first side. The lateral datum pad is formed in the top. Finally, the longitudinal datum pad is formed in the front. The single tape reel is rotatably maintained within the housing. The storage tape is wrapped about the tape reel. The leader block is coupled to a leading end of the storage tape and is selectively secured to the housing at the leader block window. With this configuration, the lateral datum pad is configured to identify a top-to-bottom position of the tape reel. Similarly, the longitudinal datum pad is configured to identify a front-to-back position of the tape reel. In one preferred embodiment, the housing is formed from a plastic material and the datum pads are molded into the housing. Regardless, upon insertion of the data storage tape cartridge into a tape drive, the datum pads are engaged by corresponding registration devices of the tape drive to precisely align the tape cartridge housing, and thus the tape reel.
Another aspect of the present invention relates to a data storage tape cartridge including a housing, a single tape reel, and a leader block. The housing is defined by a front, a back, a first side, a second side, a top, and a bottom. Further, the housing forms a leader block window, first and second lateral datum pads, first and second longitudinal datum pads, and a registration slot. The leader block window is formed at a comer defined by the front and the first side. The lateral datum pads are formed in the top. The longitudinal datum pads are formed in the front. Finally, the registration slot is formed at the front and extends along the bottom. The single tape reel is rotatably maintained within the housing. The leader block is coupled to a leading end of the storage tape and is selectively secured to the housing at the leader block window. With this configuration, the lateral datum pads are configured to identify a top-to-bottom position of the tape reel. The longitudinal datum pads are configured to identify a front-to-back position of the tape reel. Finally, the registration slot is configured to define a side-to-side position of the tape reel.
Another aspect of the present invention relates to a data storage tape drive system including a data storage tape cartridge and a tape drive. The data storage tape cartridge includes a housing, a single tape reel, a storage tape, and a leader block. The housing includes a front, a back, a first side, a second side, a top, and a bottom. Further, the housing forms a leader block window, a lateral datum pad and a longitudinal datum pad. The leader block window is formed at a corner defined by the front and the first side. The lateral datum pad is formed in the top. Finally, the longitudinal datum pad is formed in the front. The single tape reel is rotatably maintained within the housing. The storage tape is wrapped about the tape reel. The leader block is coupled to a leading end of the storage tape and is selectively secured to the housing at the leader block window. The tape drive includes a receiving frame, a rotatable drive hub, a lateral registration device, and a longitudinal registration device. The drive hub is associated with the receiving frame as configured to engage the tape reel. Similarly, the registration devices are also associated with the receiving frame. With this configuration, the lateral datum pad is engaged by the lateral registration device and the longitudinal datum pad is engaged by the longitudinal registration device when the tape cartridge is inserted within the receiving frame. In one preferred embodiment, interaction between the lateral datum pad and the lateral registration device positions the tape reel a precise distance above the drive hub. In another preferred embodiment, the tape reel has a front-to-back position relative to the housing and the drive hub has a front-to-back position relative to the receiving frame, with the longitudinal datum pad and longitudinal registration device being configured such that engagement therebetween aligns the front-to-back position of the tape reel with the front-to-back position of the drive hub. In yet another preferred embodiment, the housing forms a registration slot sized to receive a guide post associated with the tape drive for aligning a side-to-side position of the tape reel with a side-to-side position of the drive hub.
Another aspect of the present invention relates to a data storage tape cartridge including a housing, a tape reel, a storage tape, and a leader block. The housing includes a front, a back, a first side, a second side, a top, and a bottom. Further, the housing forms a leader block window at a corner defined by the front and the first side. With this configuration in mind, the first side forms a retention tab adjacent the leader block window and a notch between the retention tab and the top. The tape reel is rotatably disposed within the housing. The storage tape is wrapped about the tape reel. The leader block is coupled to a leading end of the storage tape and is selectively secured to the housing at the leader block window by the retention tab. With this configuration, the slot formed by the housing allows the data storage tape cartridge to be used with a variety of handling devices, while still properly maintaining the leader block when not in use.